If the issue is with the part design, then it is the fault of the customer if the final print does not work as expected. Tolerancing is a core tenet of mechanical design; if you brought a poorly designed part to any prototyping shop, it’s on you if things don’t work once manufacturing is done. If a print is within the allowable accuracy range (1 mm or 1%) then it’s not the Hubs fault.
Shapeways and any other larger print shop is very much what you see is what you get; as long as they deem a part printable, they will print it but that’s it. If it was printed how it was supposed to, they do not care if the design itself was incorrect.
Yes but let’s say two parts were designed to fit each other, but we’re designed improper via a hole or gap being a mm too small or too large. Diagnosing these issues before printing is nearly impossible, and the customer could argue they don’t fit due to tolerances of the hub being poor. Both of these sides of argument are hard to prove unless you are there in person. With the way 3D hubs handles refunds I could forsee it being an issue
That’s exactly my point. How could someone say what the customer shows tolerance wise is correct? It could very easily be wrong or misleading. In reality, 3D Hubs up until this point has in my opinion been running a great part just on mutual trust. If a customer requires a specific tolerance, as far as my experience goes they would specifically address this before I accepted the order, and I could respond accordingly. Same procedure as asking about infill, layerheight, material, and colour. Has tolerances become such an issue suddenly or is this merely a non existent problem being fixed. ‘Don’t fix it if it ain’t broken’. All I have to say is this is definitely going to impact customers who may have preferred just a cheap part and didn’t need tolerances greatly. It will certainly force us hubs to constantly watch our back now as an unruly customer can backlash quite easily and request an unfair refund. And I don’t mean to be Curt, but don’t respond saying all disputes are handled fairly. I have had situations before where I should not have lost money on jobs, but had to accept as 3D hubs heavily pushes for the side of the consumers. As well a fight in that situation would most likely have lead to a poor review and hurt my hub greatly. We are already at the will of the consumer, this is just giving them even more un necessary power. If a customer specifically needs a certain tolerance then I don’t see why they can’t just request this, why does 3D hubs specifically have to get involved?
To keep it even somewhat fair, Hubs would have to physically measure the part themselves. A customer could easily take the pictures at a skewed angle to warp how the print looks or improperly calibrate calipers so that the device measures incorrectly. If a Hub hadn’t measured the part themselves, they have no defense in the dispute and I don’t think this thinking is being paranoid either. It’d be a quick way for a customer to get prints completed for free, and for larger jobs, I can see this happening quite a bit. It’s very easy to edit photos, and I will not accept that as the only way 3D Hubs decides if a print order was completed correctly or not.
If Hubs wants to implement dimensional accuracy requirements, then that’s fine but you have to be able to implement it/police it fairly and provide your Hubs with the tools they need as well. I feel like a broken record here, but getting dimensions from an STL file is inaccurate and inefficient; if I need to verify dimensions are correct (which now I do), then I need to know what they are in the first place. I can only do that if the customer tells me what they are in a drawing, or if I have the parametric model. I can ask a customer for the file, but if they don’t have it and can’t clearly communicate what dimensions are required, these new guidelines will force me to turn them away. The risk is too high otherwise.
Anyone else getting the vibe that regardless of the communities concerns 3D hubs went into this conversation with the mindset they were going to do it, and rather than maybe delaying the launch to address these issues and concerns they just ignored them and launched anyway?
Unfortunately yes. The managerial speak trying to make it sound like it will benefit me as a hub and big warning across the top of my dashboard saying it’s happening tells you all you need to know.
It’s getting towards the point where I’m considering if I want to be associated with 3Dhubs as the requirements are starting to pile up for the little cash you get back from the job.
Well, as far as dimensions are concerned, any decent slicing program will report the printing dimensions of the sliced model, so there’s no need to guess. In terms of getting the prints right (accurate to those dimensions) why shouldn’t they be? I know all my prints come out well within the tolerances suggested by 3DHubs so I don’t see the concern. I always check with a customer what the purpose of their print is anyway, and if I now have to remember to also specifically ask about tolerances, that’s really no big deal - heck, we could all easily put together a stock “first question” to cut and paste for any print order that covers things like this.
To be honest, I’m not seeing a problem here. If I were a customer, not a Hub, I’d expect there to be controls like this and I’d expect the printer to deliver me high quality prints that match the model I’ve uploaded. If my model is unprintable, or I want a dimensional accuracy that’s unrealistic, then that’s another matter, but the tolerances being suggested here seem very reasonable and totally what I’d expect from a paid service.
Sorry if this isn’t a popular view, but I can’t see the problem with wanting to produce high quality prints that match the customers’ requirements. Have I missed something here? Do the majority of Hubs often print models with inaccurate dimensions? Does no one else discuss the print with their customer to get an understanding of the job and any specific challenges?
@cobnut The issue with using STL models for dimensioning is that they are dimensionless; what we get in a slicer is just the software’s representation of hundreds or thousands of triangles. Because of this curves become faceted, so if a customer has a small hole and they did not export it properly, they could easily end up with a hexagon instead of a circular hole. It’s just infinitely easier and more accurate to work from a parametric model than an STL file. It’s just poor practice in industry to dimension from STL files. To be clear, I do not have an issue with the set dimensional accuracy range or my ability to meet it. I have an issue with the complete lack of discussion as to how it’s going to be policed (sorry, but a picture won’t cut it) and the space for misinterpretation on the customers side as to what that means. I have already had to deal with customers giving me the wrong file and wanting a refund because it was “printed wrong” but the model was fundamentally wrong to begin with.
My concern isn’t hitting the targets, it’s people manipulating the system in their favour to receive free parts. Stl files Do Not show dimensions. Only overall. This will not show dimensions of inner details and walls. These new standards make it easy for someone to set a pair of calipers improperly and fight for a refund. Meeting the requirements is not at all the issue and I urge you to please read what we have discussed in the past.
